Arc Guard protection minimizes downtime in wind turbines

The arc’s temperature is so extreme it vaporizes copper conductors and creates a violent explosion

Arc faults are powerful electrical discharges that are often accompanied by an arc of electricity. The arc’s temperature is so extreme it vaporizes copper conductors and creates a violent explosion, which is extremely hazardous to personnel and equipment.

Although usually unmanned, the effects of equipment damage from an arc fault in a wind turbine is magnified by the turbine’s often remote location. Damaged turbines lose revenue until they are repaired, but repairs in a turbine nacelle at sea or on a mountain top are difficult and costly.

Far better to prevent fires and equipment damage in the first place.
Normal short circuit protection from circuit breakers and fuses will not protect equipment from arc faults, but there is still a way to minimize damage by using an extremely fast protection system from ABB that is not based on measuring electrical current in conductors.

Instantaneous detection ABB’s Arc Guard system TVOC-2 instead uses optical sensors to detect an arc flash, sending a light pulse via fiber optic cable to a monitoring unit, which instantaneously signals the incoming circuit breaker to trip.
This is a crucial function because to be effective, an arc fault must be as fast as possible. ABB’s Arc Guard system detects and transmits signals to trip the breaker in 1 millisecond. The breaker will then instantly begin to open and cut the power feeding the arc minimizing damage to the equipment and anyone working nearby.

Arc Guard consists of the arc monitor and with extensions up to 30 optical sensor inputs, which detect the characteristic light of an arc.

Reducing risk

The basic arc fault protection function is carried out in three phases – detection, recognition and action. Detection is light passing through an optical sensor; recognition is the arc monitor determining the intensity of light; action is the trip contact closing.
Plug-and-play optical sensors come in fixed lengths (1 – 60 m) and are factory calibrated. TVOC-2 is Functional safety SIL2 certified. Suppression systems like ABB Arc Guard TVOC-2 can protect anyone who may be in the vicinity of an arc fault explosion, and also greatly minimize any damage done to the equipment.

Benefits of Arc Guard TVOC-2 include lower production losses, increased operational safety and reliability, and enhanced safety for personnel. The need to repair or replace equipment is significantly reduced, and installation is easy, including retrofits.

ABB will present its comprehensive portfolio of products and integrated solutions for the wind industry during the WindEnergy Summit and WindEnergy Hamburg at #Hall 4, stand 200 from September 27-30 in Hamburg, Germany – To read more and register click here

Arc-Guard TVOC-2

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About the author

Borje Axelsson

Working with electrification products towards consultants and the Marine industry. I'm in ABB since 30+ years, with different roles in various functions. Outside work, I play guitar in a rock band and banjo&mandolin in a country band.
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